Cooling apparatus



July 27, 1937. E. F. MILLER El AL V I A V 2,088,38.

COOLING APPARATUS Filed April 2O 1954 wnuasszs: Ip VEqTOR a" RNEST ILLER,-

5 M:LLARoH.NE|.soN.

BY w,

Patented July 27, 1937 UNITED STATES PATENT OF FICIE COOLING APPARATUS Application April 20, 1934, Serial No. 721,476

4 Claims.

Our invention relates to refrigerating apparatus, more particularly to a liquid circulating system for refrigerating apparatus of the steam or vapor jet type, and it has for an object to pro- ;ride improved apparatus of the character set orth.

A further object is to provide, in refrigerating apparatus of the vapor jet type embodying an evaporative condenser, improved means for renoving condensate from the condenser and for !delivering said, condensate and unevaporated water for effecting evaporative cooling oi the con- .dnser.

In accordance with our invention, we use the condensate formed in the condenser to provide a supply of liquid to effect evaporative cooling of the condenser, preferably as a spray for wetting the air-cooled surfaces of the condenser.

We also drain the liquid which is not evaporated and add the same to the condensate before supplying the same to said spray.

A single pump serves to remove con'densate from the condenser and to deliver the condensate and additional water under pressure to the spray. The unevaporated water is returned to the inlet of the pump to be recirculated to the spray, the flow thereof being controlled by a float valve which serves to prevent the entrance of air into -the system.

The above and other objects are effected by our inventionas will be apparent from the following description and claims taken in connection with the accompanying drawing, forming a part of this application, in which: a

The single figure is a diagrammatic view, in elevation, of apparatus embodying our invention.

Referring to the drawing in detail, we show v A manifold l1 and a plurality of spray nozzlesl8 mounted thereon are provided in the upper header I 2 and arranged to direct'a spray of reirigerant liquid particles into the upper open ends of the tubes II. The refrigerant is usually water, which liquid will be referred to hereinafter without restricting the invention thereto. An ejector bodiment, to the lower header l3 through a con- 5 duit 22. Vapor for motivating the ejector, usually steam, is supplied to the ejector through a conduit 23.

V A condenser 24 is connected to the outlet of the ejector for condensing the vapor discharged 1 v therefrom, including the vapor withdrawn from the evaporating chamber and the expanded mo tive fluid. The condenser includes headers 25 and 26, and tubes 21 extending therebetween.

The headers and tubes contain the vapor to be condensed, the header 25 being connected to the ejector outlet. Suitable means (not shown) are provided for removing air and non-condensable gases from the condensing space of the condenser.

The cooling fluid, which is preferably air, is circulated in contact with the outer surfaces of the tubes by a fan 28. Viewing the apparatus as seen on the drawing, the direction of flow of the cooling-air is either forwardly or rearwardly.

To increase the cooling effect, we provide evaporative cooling of the condenser tubes. Nozzles 29, carried by upper and lower manifolds 3| are provided to spray water into the circulating air stream and onto the outer surfaces of the tubes.

Each nozzle provides a divergent or triangular spray, and the upper nozzles are arranged in al ternate or staggered relation to the lower nozzles,

so that the sprays cover substantially the entire cross-section of the air stream. The water is evaporated "bythe circulating air, thereby augmenting the cooling effect available for condensing the vapor within the tubes.

The water circulating system provides circulation of water through the evaporator III, a supply of condensate from the condenser 2| to the evaporator to replace evaporated water, and delivery under pressure to the condenser spray nozzles 29 of the remaining condensate and of unevaporated condenser spray water. The lower header l3 of the evaporator I0 is formed with a drain outlet 32 connected, through a conduit 33, to the inlet of a water circulating pump 3. The

outlet of said pump is connected through a conduit 35 to the nozzle manifold I'l.

The condensate formed in the condenser 001- .50

lects in the header 2!, which is connected to a drain conduit 36, through which the condensate flows downwardly by gravity. The conduit 36 is connected to the conduit 33, through parts presently described, for the purpose of supplying 52 having make-up water to the evaporator; that is, water for replacing that evaporated in the evaporator. The conduit 36 has a branch 38a which is connected to a float chamber 31. actuated by a float member 39 within said chamber, controls the flow of liquid from the branch conduit 360. into the float chamber. The latter is connected through a conduit 4! with the conduit 33 for supplying liquid thereto. The float valve 38 serves to control the flow of condensate to the conduit 33 to maintain a predetermined level of liquid within the float chamber 31, the valve decreasing the flow of condensate as said level tends to rise and increasing said flow as the level tends to drop. The upper part of the float chamber 31 is connected to the evaporator, at any suitable point such as the header l2, through a vent pipe 42. The same level of liquid is maintained, therefore, within the conduit 33 and the float chamber 31.

The conduit 36 is also connected, through a branch 36b, to a conduit 42', which conveys the remaining condensate to the inlet of a circulating pump 43. The pumps 34 and 43 may be gear pumps, as shown, and are desirably driven by a common source of power, such as an electric motor 40., The latter discharges water under pressure to-a conduit 44, which conveys the same to the nozzle manifolds 3|. Only a small portion of the water sprayed into the condenser tubes at one time is evaporated, so that it is necessary to recirculate the unevaporated water. This water collects in a sump 45, from which it flows through a conduit 45, a float chamber 41, and a conduit 48 to the conduit 42', in which it is added to the condensate flowing to the pump 43.

Within the float chamber 41 is a a float member 53 controlled by the level of liquid in the float chamber. The purpose of the float valve 52 is to prevent the admission of air from the atmosphere to the condenser through the water-circulating conduits in the event that the quantity of unevaporated spray water in the float chamber 41 is insuflicient to immerse the end of the conduit 48. As the water level in the float chamber 41 drops, due to any such insufliciency, the float member 53 moves the valve 52 in closing direction, thereby preventing drop in water level below a predetermined point.

The operation of the above-described apparatus, which will be apparent from the above description, is as follows: The water sprayed from the nozzles IS in the evaporator l0 flows downwardly through the interior of the tubes l4, a portion of said water being evaporated by the heat extracted from the air flowing over the tubes. The vapor is withdrawn from the evaporator by the ejector l9 and discharged, together with the expended motive fluid, into the condenser 24. The unevaporated water collecting in the lower header l5 flows by gravity 33 to the pump 34, by which it is recirculated through the conduit 35 to the nozzles l3. Due to the continual evaporation of a portion of the water, the total quantity in the circuit lust described would tend to decrease, thereby lowering the water level in the conduit 33 and the float chamber 31. The float member 39 responds to the drop in water level by opening the valve 38 to admit a quantity of condensate from the condenser 24 which is sufiicient to maintain said water level substantially constant and which replaces the water evaporated within thetubes l4.

The remainder of the condensate from the condenser flows unrestricted from the conduit 36 A float valve 38,

float valve I through the conduit through the conduit 36b to the conduit 42', in which it is mixed with the unevaporated spray water from the conduit 48 and conveyed to the pump 43, by which it is circulated through the conduit 44 to the spray nozzles 29. From the 5 latter, it is directed onto the exterior surfaces of the condenser tubes 21 to provide evaporative cooling ofsaid tubes.

The apparatus of the present case is so designed that the quantity of unevaporated spray water, together with the quantity of condensate supplied to the pump 43, may be equal to or less than the capacity of the pump, but never greater. In this case, there is no danger of flooding the condensing space of the condenser. The valve 52 operates, as described above, to prevent the entrance of air into the system when the quantity of water supplied to the pump 43 is less than the capacitythereof, in which case the pump delivers a quantity of water less than the capacity thereof.

It will be notedthat the condensate which is supplied to the evaporator as make-up to replace evaporated liquid, is withdrawn through the conduit 36a. before the portion of the condensate flowing to the pump 43 through the conduit 33b is mixed with the unevaporated spray water. In this way, the impurities and dissolved airwhich the unevaporated spray water may have acq in the spray is prevented from entering the evaporator.

The apparatus described may be used for any suitable application where air cooling or other cooling is required; for example, it may 'be in;- stalled on a railway passenger car for cooling the air therein. V

From the above description, it will be seen that we have provided vapor jet refrigerating apparatus wherein a single pump serves to remove condensate from the condenser and to provide liquid under pressure for the condenser spray; wherein the admission of unevaporated spray water into the condenser is avoided; and wherein the ad mission of air into the system is prevented.

While we have shown out invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof, and we desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

What we claim is:

1. In; vapor jet refrigerating apparatus, the combination of an evaporator, a vapor-motivated ejector for withdrawing vapor from said evaporator to effect cooling by evaporation of liquid, a condenser connected to the outlet of said ejector, means for supplying a portion of the condensate from the condenser to'the evaporator for make-up, means for delivering a quantity of liquid to said condenser to provide cooling by evaporation of liquid and including a pump which provides liquid under pressure for said coolinz and which is also effective to remove condensate from the condenser, means for conveying the remaining portion of said condensate at substantially condenser pressure to the inlet of said pump, and means for supplyng additional liquid to the said inlet of the pump and including means for reducing the pressure of said additional liquid to substantially condenser pressure.

2. In refrigerating apparatus, the combination of an evaporator, an ejector for removing vapor from said evaporator to efl'ect cooling by evaporation of. liquid therein, a condenser for said ejector, means for circulating a gaseous fluid in heat-exchange relation with said condenser, means including a pump providing liquid under pressure for spraying liquid into said gaseous fluid to efl'ect evaporative cooling of said condenser, said pump being also eflective as a condensate removal pump, a chamber arranged to receive the unevaporated spray liquid, means providing gravity flow of liquid from said chamber to the inlet of said pump, said last-mentioned means communicating with said chamber at a point sufliciently low that it is always below the liquid level in the chamber in operation,

and valve means controlling flow of liquid through said last-mentioned means and operable in response to lowering of said liquid level to decrease said flow.

3. In refrigerating apparatus, the combination of an evaporator, an ejector for removing vapor from said evaporator to efiect cooling by evaporation of liquid therein, a condenser for said ejector, means for circulating a gaseous fluid in heat-exchange relation with said condenser, means including a pump providing liquid under pressure for spraying liquid into said gaseous fluid to eilectrevaporative cooling of said condenser, said pump being also effective as a condensate removal pump, means for returning the unevaporated spray liquid to the inlet oi said pump for recirculation, and means for restricting the flow of liquid through said last-mentioned means to the available supply of liquid whereby to prevent entrance of air.

4. The combination of an evaporator, an ejector for removing vapor from said evaporator to eil'ect cooling .by evaporation of liquid therein, an evaporativecondenser for said ejector, means including a pump for directing liquid onto the air cooled surfaces of said condenser to provide evaporative cooling thereof, said pump having its inlet connected to the condensing space of the condenser and being effective to remove condensate therefrom, means for returning unevaporated 

